Friday, February 09, 2007

Murray-Darling's empty basin

The Murray-Darling summit ended yesterday in deadlock with the States failing to agree with the Federal Government's $10 billion plan to take control of Australia’s largest river system. Prime Minister John Howard and the premiers of NSW, Queensland, Victoria, and South Australia met in Canberra to discuss the proposal. The parties claimed they had made progress and plan to meet again on 23 February in order to reach a compromise.

The Prime Minister's water plan includes $3 billion to help farmers in unviable areas get out of the industry. It will also buy back water licences and return that water to the environment. The Government has also allocated $6 billion for improving irrigation technology, with the water saved being shared equally between growers and the environment. A new Murray-Darling basin authority would be created to oversee the river systems and the aquifers that lie beneath it. The authority would have five full-time Government-appointed commissioners who would report to the Federal Environment Minister. But the plan is contingent on the four Murray-Darling basin states (Queensland, NSW, Victoria and South Australia) agreeing to transfer most of their powers to the commonwealth.

Only NSW Premier Morris Iemma is ready to cede his state's constitutional rights over water. The other states have serious reservations and said the scheme was underfunded as the irrigation plan may include areas outside the basin. Howard said the states were stalling in order to inflict pain on his government and the public would lose patience with them. The PM offered concessions in yesterday’s meeting including guaranteeing existing water volumes and leaving some aspects of catchment management under state control.

Even prior to Federation in 1901, the colonies of New South Wales, Victoria and South Australia had problems managing the Murray. The boundary was the top of the bank on the Victorian side and the river was an important means of transport. When irrigation first started taking water from the river in the 1880s, it caused conflict with users of the river for navigation. The parochialism of the states meant they reached no agreements on use until a severe drought in the early 1900s. They signed the River Murray Waters Agreement to regulate the main stream to ensure that each of the states received their agreed shares of the Murray's water.

The agreement was finally superseded by the 1992 Murray-Darling Basin Agreement. The new agreement recognised the fact the river system was too big to be managed by state governments. The commission contained representatives from each of the partner governments. Ultimate control remained with each state. Just as the 1902-05 drought and irrigation problems were the catalyst for the earlier agreement, the current drought and over-irrigation has finally brought the parties together in an effort to once again beef up the commissions powers over one of the world’s great river systems.

The Murray-Darling has a million square kilometres drainage basin, 14% of Australia’s land mass. The basin drains three-quarters of New South Wales, half of Victoria, much of southern Queensland, and a small part of eastern South Australia. Although it gets a mere 6% of Australia's annual rainfall, over 70% of Australia's irrigation resources are concentrated there. Both the Murray and Darling Rivers have lengths greater than 2,500 km making the Basin one of the world’s major river systems. The Basin is in a semi-arid zone, and its ratio of discharge to precipitation is extremely low (less than 0.05) due to the evaporation rate double the rainfall rate. The situation is complicated by the large annual climate variability due to the El Nino Southern Oscillation (ENSO) on south-eastern Australia.

The basin is also important for its bio-diversity. Prior to 19th century European settlement,a third of Australia’s mammal species, half of its birds and a fifth of its reptiles were found there. Many of these species are now extinct or endangered. The basin has 30,000 wetlands, 12 of which are listed under the international Convention on Wetlands. Like the fauna, many wetlands are suffering due to human activities and some have lost half of their area.

Efforts are concentrating on understanding how to stop the river system from slowly dying. Massive demand has dramatically reduced its flow, led to the occasional closure of the South Australian ocean entrance, and added to its choking salinity. Climate change will add to the long-term problem with the elimination of Alpine snow and increasing bushfires. The University of NSW Laboratory for Ecosystem Science and Sustainability have launched a $1.7 million study into the interaction between water, soils, trees and fires in the high country. According to project lead Professor Mark Adams, unchecked bushfires create large-scale forest regeneration that uses more water than the mature forests they replace, "Research shows that the 2003 fires, for example, will likely reduce flows by more than 20 per cent for the next 20 years in the Kiewa River, a major tributary of the Murray," he said.

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